U.S. patent application number 12/834997 was filed with the patent office on 2012-01-19 for electric appliance with dual speed output.
This patent application is currently assigned to MAIN POWER ELECTRICAL FACTORY LTD.. Invention is credited to Bo Gao, Kwok Kay Lee.
Application Number | 20120014207 12/834997 |
Document ID | / |
Family ID | 45466899 |
Filed Date | 2012-01-19 |
United States Patent
Application |
20120014207 |
Kind Code |
A1 |
Lee; Kwok Kay ; et
al. |
January 19, 2012 |
ELECTRIC APPLIANCE WITH DUAL SPEED OUTPUT
Abstract
An electric appliance has first and second rotational output
spindles located within a housing. The first and second spindles
have respective first and second couplings for attachment of first
and second work tools to the first and second spindles,
respectively. The second rotational output spindle is concentric
with the first rotational output spindle such that connection of
one of the first and second work tools to the corresponding spindle
excludes connection of the other of the first and second work tools
to the corresponding spindle. The first rotational output spindle
has a first rotational speed that is different from a second
rotational speed of the second output spindle.
Inventors: |
Lee; Kwok Kay; (Hong Kong,
CN) ; Gao; Bo; (Hong Kong, CN) |
Assignee: |
MAIN POWER ELECTRICAL FACTORY
LTD.
Kowloon
HK
|
Family ID: |
45466899 |
Appl. No.: |
12/834997 |
Filed: |
July 13, 2010 |
Current U.S.
Class: |
366/100 ;
366/129 |
Current CPC
Class: |
B01F 15/0048 20130101;
B01F 7/00975 20130101; A47J 2043/04418 20130101; B01F 2215/0026
20130101; A47J 43/082 20130101; B01F 13/047 20130101; B01F 7/1665
20130101; B01F 7/00725 20130101; B01F 7/00408 20130101; B01F
7/00583 20130101; B01F 13/002 20130101 |
Class at
Publication: |
366/100 ;
366/129 |
International
Class: |
B01F 13/00 20060101
B01F013/00 |
Claims
1. An electric appliance comprising: a housing, a first rotational
output spindle located within the housing and having a first
coupling for attachment of a first work tool to the first
rotational output spindle, and a second rotational output spindle
located within the housing and having a second coupling for
attachment of a second work tool to the second rotational output
spindle, the second rotational output spindle being concentric with
the first rotational output spindle, wherein connection of one of
the first and second work tools to the first or second rotational
output spindle excludes connection of the other of the first and
second work tools to the other of the first and second rotational
spindles, and the first rotational output spindle has a first
rotational speed that is different from a second rotational speed
of the second output spindle.
2. The electric appliance of claim 1 wherein the first rotational
speed is at least three times the second rotational speed.
3. The electric appliance of claim 1 wherein the mixer has only a
single motor and the first and second rotational output spindles
are driven at the same time by the motor.
4. The electric appliance of claim 3 wherein the first rotational
output spindle includes gears driven directly by the motor.
5. The electric appliance of claim 4 further including first and
second pairs of gears and a stub-shaft located parallel to the
first and second spindles, the stub-shaft being driven from the
first spindle by the first pair of gears, and driving the second
spindle via the second pair of gears.
6. The electric appliance of claim 5 wherein the first and second
pairs of gears drive the first and second spindles such that the
first rotational speed is at least three times the second
rotational speed.
7. The electric appliance of claim 1 which is a handheld electric
mixer.
8. The electric appliance of claim 7 wherein the first work tool
comprises a mixer or beater and the second work tool comprises a
dough hook or kneader.
Description
BACKGROUND TO THE INVENTION
[0001] 1. Field of the Invention
[0002] The current invention relates to electric appliances with
dual speed outputs, and in particular to handheld electric mixers
and more particularly to dual speed electric mixers.
[0003] 2. Background Information
[0004] Handheld electric mixers consist of a housing with an
uppermost handle and a pair of downwardly extending rotational
output spindles that removeably receive work pieces for mixing,
beating, blending and or whipping food items or recipe
constituents. The spindles are driven by a variable speed motor
located in the housing via a reduction gearbox. The electronic
variable speed control can be a continuous type, in more expensive
mixers, or a stepped speed control, comprising typically 3 stepped
speeds, in less expensive mixers. Both speed control methods vary
voltage to control the motor speed. Less expensive universal motors
often used in such mixers might have a narrow speed torque range
and so exhibit poor voltage speed control over the full speed range
of the motor. This limits versatility of the mixer which ideally
should be able to achieve very low mixer speeds for preparation of
delicate food items or recipe constituents through to very high
mixing speeds for thoroughly mixing, blending, beating, whipping or
otherwise food items or recipe constituents.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a
variable speed hand mixer which overcomes or substantially
ameliorates the above problem, or at least provides the public with
a useful alternative.
[0006] According to the invention there is provided an electric
appliance has first and second rotational output spindles located
with a housing. The first and second spindles have respective first
and second couplings for attachment of first and second work tools.
The second rotational output spindle is concentric with the first
rotational output spindle such that connection of one of the work
tools to its respective spindle excludes connection of the other
one of the work tools to its respective spindle. The first
rotational output spindle has a first rotational speed that is
different to a second rotational speed of the second output
spindle. The first rotational speed is three or more times the
second rotational speed.
[0007] The mixer has only a single motor and the first and second
rotational output spindles are driven at the same time from the
motor. The first rotational output spindle has a gear driven
directly from an output of the motor. The appliance includes a
stub-shaft located parallel to the first and second spindles. The
stub-shaft is driven from the first spindle by a first pair of
gears, and the stub shaft drives the second spindle via a second
pair of gears. The first and second pairs of gears are chosen such
that the first rotational speed is three or more times the second
rotational speed.
[0008] Preferably, the electric appliance is a handheld electric
mixer, the first work tool is a mixer or beater and the second work
tools is a dough hook or kneader.
[0009] Further aspects of the invention will become apparent from
the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] An exemplary form of the present invention will now be
described by way of example only and with reference to the
accompanying drawings, in which:
[0011] FIG. 1 is an isometric illustration of a hand mixer showing
two different work tools,
[0012] FIG. 2 is a perspective illustration of the internal motor
and gear mechanism of the mixer,
[0013] FIG. 3 is a section schematic illustration of the gear and
output spindles of the mixer,
[0014] FIG. 4 is a section schematic illustration of the gear and
output spindles with a first work tool inserted,
[0015] FIG. 5 is a schematic illustration of the gear and output
spindles with a second work tool inserted,
[0016] FIG. 6 is an illustration of the different work tools for
use with the mixer.
DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0017] The entire contents of US patent publication
2009-00911199-A1 dated Apr. 6, 2009 is incorporated herein by
reference.
[0018] Before any embodiments of the invention are explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangement
of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways. Also, it is to be understood that the phraseology and
terminology used herein is for the purpose of description and
should not be regarded as limiting. In the following description a
preferred example of the invention is described as practiced in an
electric mixer, and in particular a handheld electric mixer.
However, the invention is capable of being practiced in other types
of household appliance including bench mixers, stick blender,
juicer and larger industrial mixers.
[0019] In a hand-held electric mixer according to the invention the
speed of rotation of the mixing tool, either a traditional beater
or a dough hook, is dependent upon which tool is inserted into the
output socket of the mixer. The mixer comprises dual concentric
output spindles within the tool socket so that if a tool such as a
traditional beater is inserted within the outlet socket it engages
with a first spindle and turns to the first rotational speed. If a
second tool such as a dough hook is inserted within the output
socket, it engages with the second spindle which turns at a second
speed. Thus the speed of the tool depends on the tool that is
inserted into the outlet and the motor can be driven at a
continuous speed.
[0020] Referring to the drawings there is shown a hand-held
electric mixer having an elongate body portion 1 below an
integrally formed handle portion 2. Located on a top part of handle
portion 2 is a switch mechanism 3 that is operable by the thumb of
a user in order to start and stop the mixer. The switch portion 3
may include variable speed positions for changing the speed of the
mixer as it is known in the art. On the underside of the mixer body
1 is a pair of tool outlets or sockets 6, 7 which receive work
tools such as beaters 4 or dough hooks 5. A motor 9 is located
within the housing and has an output shaft 10 which drives the work
tools 4, 5 within the outlets 6, 7 via a gear box 8.
[0021] FIG. 3 is a sectional schematic view through one of the tool
outlets, for example outlet 7. Within the outlet socket 7 is a
first rotationally mounted hollow tool spindle 11. The first tool
spindle has a concentrically mounted external gear 12 which is
driven from motor 9 by a worm gear 13 on the end of motor shaft 10.
Rotation of the motor 9 causes rotation of the first outlet spindle
11. The lower end of the first spindle 11 is a coupling 14. A first
work tool 4 comprises a shaft 16 having beating blades at its lower
end and a pair of detents 15 at an upper end of the shaft. When the
upper end of the tool shaft 16 is inserted within the socket outlet
7 the detents 15 engage with the coupling 14 in order to cause
rotation of the tool 4 with rotation of the spindle 11. The
coupling 14 and detent 15 arrangement may be of a type known in the
art.
[0022] A second tool spindle 20 is concentrically arranged around
the lower portion of first spindle 11. The two spindles 11, 20 are
mounted to be independently rotatable at different rotational
speeds. The second spindle 20 extends slight below the bottom of
the first spindle 11 and has a second coupling 21. The diameter of
second spindle 20 and second coupling 21 is larger than that of the
first spindle 11 such that shaft 16 first tool 4 passes through
second spindle 20 to engage first spindle 11 without touching
second spindle 20. Because the second rotational output spindle is
concentric with the first rotational output spindle the connection
of one of the work tools to its respective spindle excludes
connection of the other one of the work tools to its respective
spindle, that is to say the first and second work tools cannot be
connected to respective concentric spindles at the same time.
Second spindle 20 has a concentric gear 22 located about the top
part of the spindle 20.
[0023] A stub shaft 23 is located adjacent and parallel to the
rotational axis of the first and second spindles. A pair of gears
25, 26 are mounted to the top and bottom of the stub shaft 23
respectively and are fixed thereto for rotation with the stub
shaft. As second gear 24 located on and rotational with the first
spindle 11 engages with the upper gear 25 of the stub shaft 23 in
order to cause rotation of the stub shaft 23 when the first spindle
11 is driven by the motor 9. The second, lower, stub shaft gear 26
engages with gear 22 of the second spindle 20 in order to cause
rotation of second spindle 20 when the stub shaft 23 rotates. By
this gear arrangement rotation of motor 9 causes rotation of both
the first spindle 11 and second spindle 20. Through the selection
of different size gears 24, 25, 26 and 22 the second spindle 20 can
be made to turn at a different rotational speed than the first
spindle 11 for the same given motor speed. In the preferred
embodiment the speed of spindle 20 is chosen to be one-third the
speed of the first spindle 11--that is to say first spindle 11
turns three times faster that second spindle 20.
[0024] The second work tool 5 comprises a shaft 17 having blades or
a beating/kneading hook arrangement as is known in the art. At the
upper end of the shaft 17 is a pair of detents 18 having a larger
diameter than the detents 15 of tool 4. When the second shaft 5 is
inserted within an outlet of the mixer the larger diameter detents
18 engage with the second coupling 21 at the lower part of second
spindle 20 and are caused to rotate with and at the same speed as
second spindle 20. By the arrangement described if the first work
tool 4 is inserted into the mixer tool outlets then first detents
15 on the first tool 4 engage with the coupling 14 of the first
spindle and the tool 4 is rotated at the first rotational speed of
the first spindle 11. If the second tool 5 is inserted within the
same outlet of the mixer its second larger diameter detents 18
engage with the coupling 21 of the second output spindle 20 and the
second tool 5 is caused to rotate at a different, slower, speed of
the second spindle 20. In this way, the speed of the work tool
depends upon the tool which is inserted into the outlet and the
motor can be driven at the same speed. This provides a ratio
reduction based on the type of tool being inserted into the mixer
outlet without the need to physically or electronically change a
speed ratio within the mixer itself. In the current instance first
tool 4 is a beater which operates at a generally higher speed ratio
than the second tool 5 which is a dough hook for kneading
dough.
[0025] Because the couplings 14, 21 of the two outlet spindles 11,
20 are at different respective axial positions the corresponding
detents 15 and 18 on respective tool shafts 16, 17 are also at
different axial positions respective the upper or top end of the
shafts 16, 17 such that the tools have the same extended lengths
from the mixer. However, this is not essential to the invention as
it may be desired for one tool to extend further from the mixer in
order to have greater reach into the bottom of the bowl or the
like.
[0026] The above described embodiment is a hand-held mixer however
the invention is capable of application in other types of mixers
including bench mixers and larger industrial mixers.
* * * * *